Posting Reply problems

[gyro]

often, after i log into the website and then type a reply and press submit, i get a message saying "invalid session". Then when i try to go back to my typed message, it's gone. Is there any way to increase the time-out feature or at the very least, be able to go back to a typed message if something goes wrong.

[JIP]

If anyone else is seeing the same problem, please post here.
Thanks!